The Mystery of the Great White Shark's 'Superpowers'

 

The Great White Shark is the ocean's largest predatory fish, weighing over 3,000 pounds (2,268 kilograms) and reaching lengths of 15 to 20 feet or more—though it is not the largest shark species overall. This oceanic giant is often likened to an aquatic superhero; it is massive, possesses a lifespan comparable to that of humans, heals rapidly from injuries, and is remarkably resistant to cancer.

Researchers have long sought to understand the secrets behind these extraordinary traits. Finally, decoding the shark's complete genome has provided several potential explanations. A team of researchers from the Shark Research Center and the Guy Harvey Foundation analyzed the Great White Shark's genome sequence and compared it with those of other vertebrates. The findings have revealed fascinating and previously unknown details about this ancient ocean giant.

The Great White Shark's genome contains 4.63 billion base pairs—1.5 times the size of the human genome. Naturally, sequencing the genome of such a massive creature was no easy task. The shark's genome shares another similarity with the human genome: both are composed of repetitive genetic sequences. Within these repetitive regions, there are specific genetic elements known as LINEs that endow the sharks with unique capabilities. These elements frequently replicate themselves and insert copies into various parts of the genome. This process causes double-stranded breaks in the DNA, necessitating robust DNA repair mechanisms. This continuous breakdown of DNA leads to genomic instability, which can give rise to serious risks such as genetic mutations and the potential development of cancer.

However, no such reaction is observed in white sharks. Through the course of evolution, they have somehow managed to adapt to this unusual genomic characteristic.

 Just as there are genes responsible for genomic instability, the genomes of these sharks also contain genes that work to maintain genetic stability. These include DNA repair genes and tumor-suppressing genes. Specific genes—distinct from those found in other vertebrates—have endowed these sharks with remarkable capabilities throughout their evolutionary history. These specialized genes are likely a key reason why these sharks face a lower risk of developing cancer compared to other animals. Researchers suggest that such genomic stability—specifically the ability to avoid genetic mutations—is crucial for preventing cancer. Since excessive genetic mutations drive cancer development, the sharks' ability to prevent these mutations grants them a natural resistance to the disease. It goes without saying that this discovery opens up new possibilities for future cancer research. Researchers note that while simply consuming products derived from these sharks will not necessarily prevent cancer in humans, the findings could play a role in the development of alternative medicines.

Another "superpower" of the white shark is its extraordinary ability to heal wounds rapidly. This capability is also driven by specific genes that facilitate both wound healing and the maintenance of genomic stability. These sharks possess a significantly higher number of such genes compared to other vertebrates. This abundance of specific genes—which is comparatively lower in other vertebrates—evolved as an adaptation to help the sharks survive in their environment.

Researchers have identified specific genes within the genome as the drivers behind these sharks' remarkable traits. However, the research team has not yet found sufficient data within the genome sequence to fully explain one particular characteristic.

Sharks possess an extraordinary sense of smell. It is commonly believed that they can detect the scent of a single drop of blood from nearly a mile away—though this is merely a popular myth and not at all true. Researchers had expected to find olfactory receptor (OR) genes in their genome to explain this sense of smell; however, the number of such genes in these sharks' genomes is surprisingly low. Instead, researchers discovered genes known as vomeronasal genes, which are believed to play a role in their extraordinary olfactory capabilities.

The findings from this recent study will prove significant not only for understanding the genome of this white giant but also for research on other animal species. Nevertheless, researchers acknowledge that further extensive study is required; this genome sequencing has merely begun to answer questions regarding the sharks' remarkable abilities.


Sadly, despite evolving to possess extraordinary capabilities that allow them to thrive in the wild, the population of these white sharks is declining every year. Approximately 100 million sharks are killed annually, a figure that includes these massive ocean giants. Key reasons for this slaughter include harvesting their fins for soup, dubious medical research, and other factors. Often, sharks are discarded to die after their fins have been removed—a truly inhumane practice.


Movies and television series frequently portray these sharks as vicious creatures that pose a deadly threat to humans. In reality, the number of humans killed by sharks pales in comparison to the number of sharks killed by humans each year. While they have successfully survived the challenges of the natural world, surviving against human cruelty is nearly impossible—unless people come to realize just how vital these creatures are to the environment. Researchers hope that their findings will help convey this crucial truth. One can only hope that humanity grasps this undeniable reality before it is too late.